Physical review. B, Condensed matter · 1998 · 417 citations · 16 references
EngineeringMaterials SciencePhysicsCondensed Matter PhysicsMaterials PhysicsSemiconductor MaterialsIii-v SemiconductorsSemiconductor HeterostructuresSemiconductor InterfacesSemiconductor PhysicsSemiconductor SurfacesWide-bandgap SemiconductorsBand OffsetsElectronic Structure TheoryEpitaxial OverlayersGallium NitrideHeterojunction InterfacesHeterojunctionsPolarizationStrain Effects
Ab initio electronic structure studies of prototypical polar interfaces of wurtzite III-V nitrides show that large uniform electric fields exist in epitaxial nitride overlayers, due to the discontinuity across the interface of the macroscopic polarization of the constituent materials. Polarization fields require a nonstandard evaluation of band offsets and formation energies: we find a large strain-induced asymmetry of the offset [0.2 eV for AlN/GaN (0001), 0.85 eV for GaN/AlN (0001)], and tiny interface formation energies.
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